The present invention relates to an adapter structure for handheld electrical tools and, more particularly, to an adapter structure that can be connected between an electrical tool and a selective tool for fastening bolts or nuts, wherein the adapter structure can provide a torque-limiting function to prevent the bolts or nuts from being damaged.
Handheld electric tools are indispensable equipment for driving fasteners, such as bolts and nuts, to fix parts to be engaged together. In use, a turning tool can be fitted into the chuck of an electrical tool so that it can be driven by the electric tool to rotate the fasteners to fix parts together. Usually, a turning tool has a hexagonal shank at one end to be easily gripped by the chuck of an electric tool and has a fastening head at the other end, which may have various forms, such as single-blade head, cross head, and hexagonal socket, so that it can rotate the fasteners to fix parts together.
Generally, an electric tool applies a certain torque to a turning tool in a fastening operation. However, in a practical application, it is quite often for an operator to keep driving the turning tool to rotate the fasteners, even the fasteners are driven to reach their ends, thereby causing damages to the fasteners, for example, damages of the single-blade head, cross head or socket head of a bolt, or causing impairment to the appearance of the parts being fixed.